diff options
Diffstat (limited to 'sys/arch/amd64/tss.c')
| -rw-r--r-- | sys/arch/amd64/tss.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/sys/arch/amd64/tss.c b/sys/arch/amd64/tss.c index ba1b0f6..b1b5420 100644 --- a/sys/arch/amd64/tss.c +++ b/sys/arch/amd64/tss.c @@ -32,6 +32,8 @@ #include <lib/string.h> #include <vm/dynalloc.h> #include <sys/panic.h> +#include <sys/errno.h> +#include <assert.h> __MODULE_NAME("TSS"); __KERNEL_META("$Hyra$: tss.c, Ian Marco Moffett, " @@ -55,6 +57,78 @@ alloc_resources(struct cpu_info *cpu) } } +/* + * Update interrupt stack table entry `istno' with `stack' + * + * @stack: Interrupt stack. + * @istno: IST number, must be 1-based. + * + * Returns 0 on success. + */ +int +tss_update_ist(struct cpu_info *ci, union tss_stack stack, uint8_t istno) +{ + volatile struct tss_entry *tss = ci->tss; + + __assert(tss != NULL); + + switch (istno) { + case 1: + tss->ist1_lo = stack.top_lo; + tss->ist1_hi = stack.top_hi; + break; + case 2: + tss->ist2_lo = stack.top_lo; + tss->ist2_hi = stack.top_hi; + break; + case 3: + tss->ist3_lo = stack.top_lo; + tss->ist3_hi = stack.top_hi; + break; + case 4: + tss->ist4_lo = stack.top_lo; + tss->ist4_hi = stack.top_hi; + break; + case 5: + tss->ist5_lo = stack.top_lo; + tss->ist5_hi = stack.top_hi; + break; + case 6: + tss->ist6_lo = stack.top_lo; + tss->ist6_hi = stack.top_hi; + break; + case 7: + tss->ist7_lo = stack.top_lo; + tss->ist7_hi = stack.top_hi; + break; + default: + return -EXIT_FAILURE; + }; + + return 0; +} + +/* + * Allocates TSS stack. + * + * Returns 0 on success. + * + * @entry_out: Pointer to location where allocated entry + * will be sent. + */ +int +tss_alloc_stack(union tss_stack *entry_out, size_t size) +{ + uintptr_t base = (uintptr_t)dynalloc(size); + + if (base == 0) { + return -EXIT_FAILURE; + } + + entry_out->top = base + size; + return 0; +} + void write_tss(struct cpu_info *cpu, struct tss_desc *desc) { |